Low Iodine Diet

Dear OncoLink "Ask the Experts,"
I am about to receive radioiodine treatments and I need to follow a low iodine diet. Can you give me any direction? ThanksKB

Katrina Claghorn, RD, Oncology Dietitian for The University of Pennsylvania Health System, responds:

The point of a low iodine diet is to deplete the body of it's natural stores of iodine which makes the radioactive iodine treatment more effective. The premise is that when the radioactive iodine is administered the thyroid will "suck" up the iodine because it has been so depleted.

It is very important to note that every institution and physician has their own guidelines. Some require an extremely restricted iodine intake. Some doctors like their patients on this diet for as long as two weeks while others have them on it only a couple of days preceding your diagnostic scanning procedures and treatment. The purposeof thisdiet is to enhance your scanning and treatment. If you receive radioiodine therapy, the diet should be maintained until two days after your treatment.

Iodine is used in the care and feeding of animals, as a stabilizer and/or safety element in food processing, and as a component of red food dyes. Many salt preparations are also supplemented with iodine. Therefore, it may be found in varying amounts in all foods and beverages. The richest sources appear to be iodized salt, dairy products, fish, processed meats, pudding mixes, candies, frozen dinners, "fast" food, and foods containing artificial colorings.

This diet is deficient in calcium because all dairy products must be avoided due to their high iodine content. Calcium supplementation with 1000-1200 mg of calcium carbonate is, therefore, recommended.

Below is the diet recommended at The University of Pennsylvania Medical Center. Again, please check with your physician and/or registered dietitan to make sure the diet is right for you.